While most young children in the United States have received vaccinations against Bordetella pertussis since the 1940s, in recent years “whooping cough” has made a comeback.
Many in public health believe an increase in pertussis cases over the past decade is partially the result of waning immunity 5 to 10 years after vaccination, leaving adolescents particularly vulnerable and creating a potential reservoir of infection in adults. This pertussis reservoir in turn increases the risk of disease transmission to highly vulnerable unvaccinated newborns. The approval in 2005 of two new combination booster vaccines means that now almost all adolescents and adults will be able to be protected against pertussis infection.
Mitka M. Age Range Widens for Pertussis Vaccine. JAMA. 2006;295(8):871-872. doi:10.1001/jama.295.8.871